MCDB 423 Lecture Notes - Lecture 2: Sister Chromatids, Mitosis, Lac Operon

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purplebeaver856

5 May 2017

School

U of M

Department

Molecular, Cellular and Developmental Biology

Course

MCDB 423

Professor

John Kuwada

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Document Summary

Their embryo is 10x the size so the cells are easy to manipulate. The embryo consist of a brain and many ganglia which are mini-brains that consist in many segments of the body. Each of these are given rise to by a segment of the neurogenic region where of it that contains a 150 ectodermal cells. This is a hemi-segment of the neurogenic region. So when it divides, one of its progeny will always be a neuroblast. They are also unique because each of these neuroblast gives rise to a specific subset of the neurons in the thoriac section as an example in this case. The(cid:455) are arra(cid:374)ged i(cid:374) ro(cid:449)s a(cid:374)d (cid:272)olu(cid:373)(cid:374)s (cid:449)hi(cid:272)h allo(cid:449)s us just (cid:271)(cid:455) looki(cid:374)g at the(cid:373) to sa(cid:455) it"s neuroblast 1-1, 1-2, 1-3, etc. Each neuroblast gives rise to a unique collection of neuron. It gives rise to two progenies where one of them is a neuroblast 1-1 again.

Related Questions

1. CAN BE MORE THAN ONE The arthropods are the most successfulgroup of animals; several key features explain their success. Checkall of the features that one would use to classify members intothis phylum.

growth takes place throughecdysis

a rigid exoskeleton made ofchitin

closed circulatory systems

jointed appendages

a rigid exoskeleton made ofkeratin

segments specialized intofunctional tagmata
2. An entomologist observed a locust sitting on a branch pumpingits abdomen like an accordion. What is the insect doing?

Stretching out its pedipalps

Assisting gas exchange in thetracheal system

Speeding the flow of blood throughits veins and arteries

Clearing its spinnerets

3.Dibenzoylhydrazines are a category of molecules that have beenused as insecticides. They work by blocking ecdysteroid receptors.How does this kill an insect?

The chitinous exoskeleton isdissolved.

The insect can no longer excretenitrogenous wastes.

The insect can no longer coordinateits movements.

The insect cannot molt.

4. The grasshopper equivalent of an ear is found

on the side of its head.

on the abdomen.

Grasshoppers do not have afunctional equivalent to ears.

directly behind the antennae.

5. A snail in your garden and an oyster are quite different inappearance. What would be evidence to justify grouping themtogether?

Both have a mantle capable ofsecreting calcium carbonate.

Both use siphons to obtainoxygen.

Both have sensory antenna.

Both use a radula for feeding.

6.Barnacles are sessile filter feeders but unlike bivalves theyhave internal fertilization. How do they solve this problem?

They are only capable of asexualreproduction.

The filter sperm from the watercolumn.

They are hemaphrodites withespecially long penises.

They get fertilized during free living larval stages.

7. Bivalves lack a radula. How dothey eat?

The gills filter water and extractorganic matter.

The mantle traps and moves sedimentto the stomach for digestion.

Inhalent siphons suck water intothe mouth.

Most bivalves have photosynthetic endosymbionts in the visceralmass.

8.If a marine biology student discovered a dorsoventrallyflattened marine worm, what would be an effective way to determineif the specimen was a flatworm or a ribbon worm?

Examine the morphology of theexcretory system.

Look for a head at the anteriorend.

Determine the number of embryonicmembranes.

Look for an anus.

9.Inside its beak an octopus has a rasping tongue that is usedto tear apart food, which gastropod structure is this analogousto?

Nephridium

Radula

Shell

Mantle

10.Pinworm is spread by contact, and the worms cause severeitching around the anus. Why is it so common?

Insect vectors spread thedisease.

The intense itch produces anintense desire to scratch.